The BQ25071DQCT is a highly integrated linear LiFePO4 Battery Charger targeted at space-limited portable applications. It accepts power from either an USB port or AC adapter and charges a single-cell LiFePO4 battery with up to 1A of charge current. The 30V input rating with 10.5V input overvoltage protection supports low-cost unregulated adapters. It has a single power output that simultaneously charges the battery and powers the system. The input current is programmable from 100mA up to 1A using the ISET input or configurable for USB500. There is also a 4.9V ±10% 50mA LDO integrated into the IC for supplying low power external circuitry. The LiFePO4 charging algorithm removes the current taper typically seen as part of the constant voltage mode control used in Li-ion battery charge cycles which reduces charge time significantly. Instead, the battery is fast charged to the overcharge voltage and then allowed to relax to a lower float charge voltage threshold.
Single cell LiFePO4 charging algorithm
Programmable charge current through ISET and EN terminals
